Various types of parts cleaning machines are known in the trade. One type of parts cleaning machine is known that includes a reservoir with two tanks, one containing wash solution and the other containing rinse solution. The basket is movable between a loading position, a cleaning position, and a rinse position. When the basket is in the cleaning position inside the reservoir, it is alternately rotated in opposite directions. An example of this type of parts cleaning machine is found in U.S. Pat. No. 5,368,053 to Wilson.
Another type of parts cleaning machine, as shown for example, in U.S. Pat. No. 3,645,791 to Sadwith, includes a platform rotatable in a housing, with parts to be cleaned supported on the platform and with a plurality of nozzles positioned in the housing for spraying streams of water on the articles to produce a scrubbing, scouring, or lifting effect on dirt and foreign matter present on the articles being washed. Since the parts to be cleaned are stationary on the platform, cleaning of irregular shaped parts is sometimes difficult and a relatively large number of spray nozzles and a relatively large volume of cleaning solution or wash solution is need to try to reach and clean all surfaces of the parts to be cleaned.
U.S. Pat. No. 5,197,500 to Diamond discloses a combustion chamber cleaning machine including a revolvable main turntable having a plurality of individual minor turntables for supporting the combustion cylinders and rotating them. The drives and controls for the main turntable and the minor turntables are relatively complex and costly.
In U.S. Pat. No. 5,666,985 to Smith, there is shown a programmable apparatus for cleaning semiconductor parts which includes a chuck mounted on a rotation mechanism rotatable around a first axis and the element to be cleaned rotates around a second axis spaced from the first axis in a planetary member. The drives for the main turntable and the minor turntables are subject to contamination because of their location in the cleaning chamber.
It is known in multi-stage rotary washers to transfer parts along a circular path. After a part is loaded in the housing of the rotary washer, the transfer mechanism indexes the part into the first station of the rotary washer. Each successive index transports the part to the next station. Eventually, after passing through each of the processing stages, the washed part reaches the unload station, where it is removed from the rotary washer. The transfer mechanism rotates about a single axis. Because of this, liquid solution spray nozzles and air blow-off nozzles, which are used to clean, rinse and dry, respectively, have to be positioned in numerous locations throughout the processing stages. Numerous nozzles are needed to assure that wash and rinse solution and air impinge upon critical surfaces multiple times, for cleaning and drying of the parts.
The known multi-stage rotary washers have several drawbacks, however. The equipment footprint is large, that is, the rotary washer occupies considerable floor space, and the equipment itself is relatively complex. Thus, there exists a need for an improved multi-stage rotary washer for cleaning parts which is relatively compact and obviates deficiencies and disadvantages of prior art rotary washers.
Other objects and advantages of the present invention will be made more apparent in the description which follows.